The Lost Moons are characters introduced in New Moon. It has not been made clear to which planet or planets they belong.
The Lost Moons are similar to the moon, though a bit smaller. They have white eyes, are grey, and appear to be made from cheese as well. Even though there are three of them, each one have a bit different appearances. The first moon has eyes close to each other and a smile, the second moon has its eyes in the top of its head and is sticking out its tongue, and the third moon has a smaller smile and its eyes are afar from each other.
The Moons were caught by the space mice as well, and were later rescued by the moon. They appeared to be very energetic and love to "smash stuff", and appear to be young.
They appear on level 8, the only level that has more than one planet to be rescued. They are trapped below the ground, and the player has to turn a wheel to free them. They follow the player, and even though they usually stay together, one or more of them may scatter away from the other ones, but can be easily recovered.
Like with other planets, the game will show the icon if one of the Lost Moons is not in the screen. Only one icon will be showed even if there are more than one off-screen Lost Moon.